These early termination fees can cost hundreds, if not thousands of dollars to quit a cell contract before it's up. With T-Mobile swooping in and reportedly ready to cover these costs could be the final catalyst in many subscribers' troubles with the big three U.S. cellular giants into moving to the smaller network, which seems hellbent on shaking up the wireless industry for the benefit of the end-customer.

Under the terms of the deal, according to the mobile publication, up to five lines can be traded in with the early termination fees covered. This includes all devices — including hotspots and mobile phones — tied to a particular contract.

That leaves the customer without any devices to speak of. Deviceless new customers will be allowed to buy devices from T-Mobile's own range, but will not be able to bring-their-own-device akin to other schemes.

It may not be financially viable, with some fees failing to offset the cost of acquiring new devices. But the benefits T-Mobile has already dished out to existing and new customers may make the deal sweeter — such as the new plan structure for new customers, dubbed "Uncarrier," which all but killed off contracts and phone subsidies, and its unlimited international data roaming plans under the "Simple Choice" moniker.

This would be painful for AT&T and others to swallow — despite AT&T's attempt to get there first on a similar line of thinking.

The largest U.S. carrier by subscribers earlier in January said it would offer up to $450 per line to T-Mobile customers switching to AT&T. But in ZDNet's Matt Miller's case, the math didn't add up — paying just $130 for five phones on T-Mobile.

T-Mobile is holding a press conference at CES 2014 later on Wednesday. We'll have more when it lands.